Refer to the computer output of Exercise 11.21.a. Locate the value of the t statistic for...

Refer to the computer output of Exercise 11.21.

a. Locate the value of the t statistic for testing H0: β1 = 0.

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b. Locate the p-value for this test. Is the p-value one-tailed or two-tailed? If necessary, calculate the p-value for the appropriate number of tails.

Exercise 11.21

A firm that prints automobile bumper stickers investigates the relation between the total direct cost of a lot of stickers and the number produced in the printing run. The data are analyzed by the Execustat computer package. The relevant output is as follows:

a. Plot the data. Do you detect any difficulties with using a linear regression model? Can you see any blatant violations of assumptions? The raw data are as follows:

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b. Write the estimated regression equation indicated in the output. Find the residual standard deviation.

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c. Calculate a 95% confidence interval for the true slope. What are the interpretations of the intercept and slope in this problem?